In practice it is necessary, in the case of load cells, to provide an overload protection in order to prevent destruction of the load cell if the load is too high.
An overload protection for a load receptor of a load cell is known from DE 10 2004 027 619 B4. The load cell shown has two parallelogram links which are arranged in a load beam and are formed by recesses arranged underneath the parallelogram links. Between the recesses, a limiting element is arranged which has a narrow, end-face pin which engages in a recess of the movable part of the load beam. The pin has a concave contour which is adapted to round alignment pins. The alignment pins are inserted into a receiver arranged on the movable part of the load receptor and secured there. The diameter of the alignment pins determines the free path of the movable part of the load receptor. This load beam is relatively expensive to produce because it is necessary to adapt the dimensions of the alignment pins and the outer contour of the pin to each other very precisely and only very small tolerances are admissible during assembly.
EP 0 251 175 A2 shows a load receptor of a load cell which has four through holes transverse to its longitudinal extension. These four through holes are connected to each other by slots. A slot extending in the force application direction has a contour which extends transverse to the force application direction in sections. Because of the contour extending transverse to the force application direction, this slot represents an overload protection. During the production of this load beam it is necessary to form relatively long thin slots which are allowed to have only a very small tolerance. This load beam is therefore relatively expensive to manufacture in terms of production.
U.S. Pat. No. 6,755,087 B2 shows a load receptor of a load cell which likewise has four recesses which are aligned transverse to the longitudinal extension of the load receptor. These four recesses are again also connected to each other via slots. These slots likewise extend over a very long distance, with the result that this load beam is also relatively expensive to produce.